Uhh, unless that's how his family pronounces the name.
Judging from the rest of his behavior and the mental signs that have gone with it, it would not be surprising at all if he doesn't have a clue regarding the correct pronunciation of his own surname.
shy-voh, shy-ster... has a ring to it
< Uhh, unless that's how his family pronounces the name. >
My cousin's name is Yvonne. She answers to Ya-vonne. She is very proud to "correct" people who address her as E-vonne.